The ideological purposes of radio broadcasts are presented by the government in quasi-cold war terms. One radio commentator, Lyuben Popov, has described the radio as a weapon for waging war on the air. He explained that "the struggle on the air is becoming sharper and sharper and more and more uncompromising.... Our propaganda work is part of the ideological struggle for victory of communist ideas." Radio is perceived as serving two principal ends. On the domestic level it serves to provide information as well as propaganda to the public; on the international level it functions in a purely ideological capacity.
There are twelve mediumwave radio transmitters: two are located in Pleven; two in Kurdzhali; two in Sofia; and one each in Plovdiv, Blagoevgrad, Varna, Shumen, Stara Zagora, and Stolnik. There are eleven ultra-shortwave stations: three are located in Sofia, two in Botev, two in Slunchev Bryag, two in Kyustendil, one in Snezhinka, and one in Plovdiv. There are four shortwave radio stations in Bulgaria. Of the total number of twenty-seven radio stations in the country, six broadcast in both amplitude modulation (AM) and frequency modulation (FM); twenty broadcast in AM only; and one located at Botev Peak broadcasts only in FM.
Bulgarian radio stations are on the air approximately 500 hours per week. Foreign broadcasts are transmitted approximately twenty-six hours a day Monday through Saturday and twenty-nine hours on Sunday. These programs are broadcast in Bulgarian, Turkish, Greek, Serbo-Croat, French, Italian, German, English, Spanish, and Arabic and are transmitted to Europe, the Middle East, Africa, North America, and South America. The number of domestic listeners has approximately doubled over the 1960-71 period. In mid-1973 over a quarter of the population owned radio sets.
The leading radio programs are transmitted by Radio Sofia. Radio Plovdiv, Radio Varna, and Radio Stara Zagora also transmit popular programs. Radio Rodina is the main station transmitting to Bulgarians residing abroad. Generally, radio programs consist of news bulletins dealing with both local and international events; programs for rural listeners and industrial workers, which deal with industrial, agricultural, and cultural matters; programs for children, which complement the formal educational curriculum; literary and cultural programs; and scientific programs.